Combined time and temperature control



Aug. 26, 1930.. R. D. SMITH 1,773,883

COMBINED TIME AND TEMPERATURE CONTROL v Filed April 21, 1927 Patented,Aug. 26, 1930 PATENT OFFICE f RAYMOND D. SMITH, OF PLEASANTVILLE, NEWYORK 'I COMBINED .TIME AND TEMPERATURE CONTROL Application 1ed Apr1`21,

This invention relates v'to the automatic control of the flow of gas orother medium sus-.

ceptible of variation in its rate of flow 4by altering the capacity ofits conduit to permit 5 such flow and by degrees, such for example as iseffected by the opening and closing of a.\valve in a pipe line orbyofthe increase and decrease of resistance in an electrical line; andparticularly concerns the operation of a l0 valve or other low controljointly by timing mechanism and by heatsensitive mechanism or by eitheralone when desired.

An illustrative embodiment of the invention is hereinafter described andclaimed with particular, though not exclusivereference to an applicationof the invention wherein the main heating burner of a gas oven, waterheater, or the like, may be controlledselectively or jointly by timemechanism and b v an yassociated thermostatic mechanism sensitive to thetemperature in the oven or in the water being heated.

Reference is had to the accompanying drawings in which: Fig. 1 shows in'side elevation and partial` ly in section a ossible form of valve andits actuating K mec ianism including time and thermostatic controlstogether with an oven and its main burner part of the 'mechanism beingbroken away to make room for:

Fig. 2,/which is a partial plan view lookinfr downwardly on certainparts of Fig. 1.

ig. 3 shows a modification of the construction of the valve mechanism.

Fig. -t-shows a specific modification part of the 'valve mechanism ofFig. 1.

' Throughout the drawings different views of the same part aredesignated b v the same reference numeral.

As the time controlled mechanism employed in this improvement ma)v be ofany kind desired I have chosen herein to illustrate a timing mechanismidn'tical with that in mv co-pending application Serial No.

of a herein need only explain that upon approlpriate setting of timepointers 101 and 105 feeler levers 70 and 71 respectively are locked inposition to intercept the rotative movement of arms 47 and laterunlocked manually or 157,733, and for the purposes of description 1927.Serial No.v 185,563.l

by running of the timev movement 99 as desired thereby to free arms 47.

When the arms 47 are intercepted they occupy one or another of fourequally spaced points in their circular travel being advanced from oneto another of these consecutive positions in ninety degree increments oftravel b v the handle 62 as eifected against the resistance of thedetent roller 2 which normall v seats itself in-the crotch between`successive teeth ofthe four'pointed star wheel 41 whereby.v arms 47receive their normal definite positioning as aforesaid.

Gear 53 turns fixedly with arms 47 and is in mesh with pinion 5-1 faston fthe crank 30 so that each quarter revolution of arms 47 produce ahalf revolution of crank 30 where.

'by valve 10 is alternately opened and closed upon respective quartervturns of handle 62 except when feelers or 71 are locked b v the timingmechanism in which event arm 47 is held from rotating with handle 6'2which latter consequently advances and is held in a position energizingband spring 5l to cause later, time controlled escapement of arm 47`automatically to actuate the valve.

As thevabove described details are not y material to the` presentinvention it will suliice to consider valve 10 openable and closeablc byhandle 62 with or without the medium of time control and through thefollowing mechanism which is more particularly concerned `with thepresent improvement.

Valve 10 consists of a body portion containing the dividing partition 13in which isthe orifice 1-1 to and away from which the piston 19 may bemoved b v vertical sliding of the stem 17 loosely guided in the bonnet16 and steadied at its lower extreme end 1S b v a guide boss- -formed inthel valve casting.

Stem 17 is slidable up and down in response to actuation by 'the timingmechanism hereinbefore describedand is turnable on its axis by the heatcontrol mechanism next to be described: either of which movements ofstem 17 causes upward or downward movement of piston 19 .relative toorifice 1-1.

The vertical 'up' and lown movement of stem 17 is accomplished b v theconnecting bail 29 hinged` on the eccentric portion of crank 30 andpivotally engaging a collar'58 freely slidable 0n stem 17 and serving totransmit the upward pull of bail 29 through the medium of compressionspring 56 acting between collar 58 and the enlarged head 57 of stem 17and serving to transmit the downward thrust of bail 29 through themedium of compression spring 59 acting between c0llar 58 and the .lowerthrust washer 60 be` neath which is .pinned rigidly to stem 17 theIlong, small diameter gear 112 which remains in mesh with a segment 113Whatever the vertical position of stem 17, the teeth of gear 112 freelysliding through the teeth of segment 113 in the up and down movements ofstem 17. The portion of stem 17 nearits bottom end whereat is carriedthe piston 19 is formed as a screw 114 to lit a correspondingly threadedhole in piston 19 which latter is kept from rotating by the fact of anotch 115 being engaged by a fin 116 projecting from the interior wallof valve 10 so that upon rotation of stem 17, piston 19 being thus heldfrom rotatingr will instead. work either upwardly or downwardly on'tliescrew portion 114 of stem 17. Stem 17 further carries at a fixed pointthereon the auxiliary seal piston 117 whose function is in theuppermostposition of stem 17 to press against the bonnet seat 24e toseal the stem opening through the bonnet against possible escape of gaswhen piston 19 is absent" from its seat 22.l v

There remains to be described the mechanism by which segment- 113 isswung to etectthe opening or closing movement^of piston 19 to a degreecorresponding to some. temperature it may be desiredto maintain in say,an oven, the wall of which I have indicated at 118. vSuch oven may beheated by burner 119 having ports 120 and supplied with gas through theorifice 121 as regulated by piston-19 in its movements to and from theseat l22 of valve 10. Entrance for the air to lnix with the gas sodelivered through'oritice 121 is provided by openings 122 which may beadjustable to regulate the mixture in the. usual way. i

A pilot burner 123 maybe positioned to ignite the burner 119 and deriveits supply of gas through a-tube 124 connected into the supply' side ofvalve 10 so that pilot 123 may remain permanently burning irrespectiveof whether valve 10 is open or closed.

I may mount a bracket 125 on Vthe housing of the timing mechanism whichis supported by the'valve body 35 or on the oven wall 118 which with alower bracket 126 will afford bearing for `the upright shaft 127 vpinnedt0 segment 113 for rotatingv the same and carrying at its upper end acam 128 and hub 129 of which is likewise pinned to shaft 127. The upperbracket'125 carries a mounting 130 in which is mounted by threadedengagement the thermostatic tube 131 of/expansible ma- 1,773,aaa

terial such as copper or brass at the opposite end of which 1s rigidlysecured one end of a relatively non-expansible element or rod 132 ofporcelain orV other suitable material 4 which may slide in a bearing inbracket 125 and have its opposite end thus guided in accurate positionto act upon cam 128, the latter having a rotative tendency imparted toit by spring 133 keeping it closeted against the end of rodn 132.Rotation 4of tube 131 by means of the graduated vwheel 134 will shiftthe position of tube 131 longitudinally becausepof it-s threadedmounting and thereby vary the action of rod 132 in its positioning ofcam 128, hence segment 113, hence the vertical position of piston 19 onvalve stem 17 and this effectmay 5be indicated by a. stationary pointer135 as is common practice in the art of heat regulated valves.

The operation is as follows:

Fig. 1 shows valve 10 closed because of the position of handle 62 andthe crank 30.

Therefore no gas is delivered to burner 119,

oven 118 is cold, thermostatic tube 131 has shortened overcoming spring133 swinging segment 113 clockwise in Fig. 2rotating gear 112 contraclockwise in Fig. 2 thereby pulling piston 19 as far upwardly on thethreaded portion of dem 17 as it is designed to go,l spring 59compensating to avoid any positive ]am of piston 19 downwardly againstits seat- 22. yvalve by a quarter turn of handle 62 either directlyresponsive to such handle movement or consequent thereupon after anintervening period of time if we choose to make use of the timingmechanism hereinbefore descibed.- The resulting quarter turn of ear 53results in a half turn of pinion 54 w ich shifts crank 30 to itsuppermost or dotted line position thusraising valve stem 17 and piston19 to open orlfice 14 all of which movement is transmitted through thecompression spring 56 on the-valve stem by the tension in which,auxiliary or seal piston 117 is brought against the bonnet seat 24. Inthis position of parts a full supply of gas is delivered through oritice121 to burner 119 which ignites from pilot f 123 and proceeds to heatoven 118. As the temperature rises tube 131 expands drawing rod 132 tothe right permitting contra clockwise rotation ofrsegment 113 underaction of Yspring 133 in Fig. 2 which turns gear 112 and hence stem`17clockwise in Fig. 2 which by the action of screw threads 114 in piston19 gradually forces the latter downwardly to check the flow of'gasthrough orilice 14 against the action of spring 133 until finally theconsequent reduction of gas supplied to burner 119 reduces the oventemperature to a. point where the consequent cooling of thermostatictube 131 swings the rotatingiparts in the op- Let us now open theJposite direction and turnsy screw 114 likewise Y in the oppositedirection to increase the supply of gas throughoritice 14 by againraising piston 19; this compensating action re-occurring in respectivelyalternate directions to the effect of maintaining the temperature inoven 118 at approximately the designed point indicated-by pointer 135on'the graduated wheel It will be understood that in any Condition ofthe heat 'control of` piston 19the latter may always andvatl any time beclosed vdownwardly against its seat by dropping of stem ,-17 either bydirect manipulation of handle 62 or through the intervention of timecontrol in association therewith and that in no case will this result instrain or jamming of the several mechanical parts for if stem 17 begiven a tendency to drop at a time when the' rotative position of stem17 as caused by heat control had run piston 19 rather far downwardly onthreads 114 thus preventing the full drop of stem 17 handle 62 cannevertheless be rotated to and held in its valve closed position theactual dropping of stem 1 7 and corresponding rotation ofcrank 30 beingdeferred until the. cooling of the oven swings the heat controlled partso that stem 17 turns in its threaded engagement with piston 19- as thecooling ofthe thermostat causes this turning followed up by a gradualdropping of stem 17 under the impulse of band spring 51 until thenormally closed position of valve 10 with the thermostat 'cool obtains'as pic tured in Fig. 1. Y j

It should be explained that the ability of the crank 30 to raise andlower stem 17 without'binding or cramping, regardless of the verticalposition `of piston .19' on its threads 114, is well' accomplished bythe yielding ofl y compression spring 59, alone, and without dey gear53er crank 30, the handle 62 could still .pendence on the backwardyielding' of band spring 51 so that if the latter failed to func.- tion,orl in fact were entirely omitted in the design and in its stead a rigidoperating connection established between handle 62 and be manuallypositioned at its definite stations determined by lstar wheel 41 androller detent 42, alternately sealing and unsealing orifice 24 by meansof seal piston 117 lwhich in Fig.`

1 is shown pinned tostem 17 and in Fig.l 4 not so pinned butpermittingvalve stem 17 yto. rotate for theheat control function'without corresponding rotation of seal piston 117 whenr` the latter ispressed upwardly against seat 24.' Escape of gas is efectually sealed bypressure against stem 17.1of the relatively soft washer made of leatheror other suitable material carried in the recess inl the upper face ofpiston 117 which contactswith seat 24whether or'not stem` 17 has .anyother tluidstight packing in its bearing in valve bonnet 16.' P e ATheadjustment for operation is preferably y such as-to make' it impossiblefor piston 19 to bescrewedupw'ardly far enough to lift same away4 fromits seat 22 by any action of thermostat 131-132 unless the seal piston117 is upwardly positioned against its seat V24; this precluding escapedgas between stem 17 and its bearing hole in .bonneti16 should 'nopacking at that point be employed.

c To make the opening and closing of orifice 14 a more gradual functionof piston 19 in its movement I may form the latter as a cone as shown at19 in F ig. '4 and the seat to correspond if desired.

In theforegoing I have shown how a single valve may be subjected to a.combination of v control by timing mechanism and by heat sensitivemechanism throughv the joint and separate actions ofsuch two mechanismsa single movable element of the valve. In `Fig.v 3 I show how a singlevalve may be subjected to this combination of control in4 an arrangementwhere the timing mechanism Aoperates one movable element of the valve.and the heat governed mechanism operates a"l separate` associatedmovable member ofthe same valve.

In Fig. 3 the burner is indicated at 140 having ports 141l and entrancefor the air'.

through openings 142 in "the mixture adjusting cap 143. Gas is ledto'burner 140 through threaded mounting and-with it the valve seat 148carried at vitsbottom end into the opening ,149 of which the point of aneedle valve 150|may project, this needle valve comprising` the bottomterminus of the valve stem 17 bail 29 just asin the, case of stem 17 inFig. l. The operation of this modification pictured in Fig. 3 is asfollows.' Gas delivered'through the conduit opening 145 isadmittedthrough ports 151 kin the wall of'valve housing 146 r and is conductedthrough flutes 152 cut in the lower part of stem 17 vto the interior.cavity 153 of the housing 1,46 and there retained i or hence permittedto 'lowbut into burner 140 `through orifice 149 depending on whetherneedle 150 is closeted againstv its seat. Obvioperated upwardly anddownwardly by the ou'sly the alternate lifting andlowering "of" stem17through the connection of bail29 as actuated byA crank 30, respectivelyopens I and closes orifice 149 to deliver or shutoff ga-s -from burner140. If stem 17 `be'lifted and needle valve'150raised from its seat 148the supply ofl gas permits burner 140 to heat oven' 118er anyother'desired compartmenta,

or medium, ormaterial to'which thermostatic tube 131l is sensitivewhereupon the .Iva

consequent movement or swing of Segment 113 rotates valve housing 146 sothat the needle seat 148 screws upwardly toreduce the amount of openingbetween needle valve 150 and said seat which will cut down the 'supplyof gas, reduce the temperature acting upon tube 131 which in turn willoperate segment 113 to screw housing 146 downwardly yagain and increasethe supply of gas to burner 140 whereby an approximately constanttemperature will be maintained in whatever is heated by burner 140, thattemperature being determined by the setting of graduated wheel 134 asinthe case of the arrangement shown in Fig. 1 It willbe obvious to thoseskilled in the art that the timing mechanism and the thermostaticmechanism may be of any of numerous styles and that their positionalrelation to each other, to the controlled valve, and `to the oven 118 orother device to be heated may be varied at will. It will also beunderstood that thev present invention is in noway limited to any of thedetails of construction herein disclosed to illustrate a pos'- Msibleembodiment and that the following t claims are not intended to limit theclaimed combinations to any of the particular devices and arrangementspictured and described.

Among the departures and modifications possible the following mentionwill bev clear. I may arrange a `timing mechanism 'to automaticallyunder time control vary the setting lof graduated wheel 134 or othermeans for varying the temperature at which oven 118 will beautomatically maintained by the heat sensitive vdevice 131, 132. Thiswould be useful for instance, in the cooking of foods where, after adesigned initial period of cooking at vrelatively high temperature the ytime mechanism would automatically operate to shift the setting of wheel134 and cause the Ioven thereafter to be maintained at a lower constanttemperature for finishing the cooking, after vwhich the gas may beentirely sliut off byy second automatic action of thel timing mechanism.

I may 'substitute-an electric switch to control the current to anelectric heating unit that will take the lplace vof burner 119 andarrangeelectric contacts f such a switch to be alternately closed andopened by the vertical movements of stem 17 subject t`o time control asherein and I may provide a rheosta-t f to be caused to introduce.varying degrees of resistance or to produce` other electricaleli'ects'designed to vary the heat given,oi by the said unit consequentupon the rotative movement of stem 18 under the action of thermostaticdevice 131,132. l

I may further insure against the escape o I gas elsewhere than intoburner140 in Fig. 3

by housing the entire mechanism or `any convenient' parts thereofexterior of burner 140 in a 'gas tight enclosure asis common in the art.v l

I may within the scope of this invention employ la timing mechanismofthe type disq I have chosen todisclose operates at one man- 4ual settingautomatically to turn onthe gas and to shut oil `the gas at any twoseparate and selected times 1n the period between which the theremostatwill maintain the oven heat at a set temperature. The inventiontherefore contemplates the starting of cooking ata predetermined time asdetermined y by time mechanism, the control of that cooking as totemperature lby-automatic thermostatic means and the stopping of thecooking y again by timing mechanism. It is equally within the scope ofthe present improvement however, to provide that the timing mecha- .nismshall alone turn on or shut olf the gas and that if a timing mechanismis employed capable only ofturning on the gas the heat control may bearranged merely to turn oil' the gas and keep it turned off upon theattainment of al certain `critical temperature the subsequent loweringof which will notv operate 'the thermo open the valves.

` 1. In a valve, in combination, a seal piston,

-dynamic means to rea stem longitudinallyslidable in a bearing tooperate said seal piston, a seat to be contacted by escape o gas throughsaid bearing, a flow governing piston` operated by said stem in relationto said seal piston and to said seat, and heat sensitive means arrangedto operate said `flow piston without displacing said seal piston fromits seat.

2. In a valve, in combination, a seal piston, a stem lono'itudinallyslidable in a bearing to said piston for preventing the operate saldseal piston, a seat to be contacted by said piston for preventing theescape of gas through said bearing, a flow ,governing plston operatedbyturning movement of, said Stem, hand actuated mechanism arranged toslide said stem, and heat operated mechanism arranlged to rotate saidstem. c

3.- n a valve, in combination, a seal piston, a stem lonitudinallyslidable in a bearing to operate said seal piston, a seat tobe contacted by said piston for preventingthe escape of gas through saidbearing,l a flow governing rsaid valve part and said thermostaticdevice.

thermostatic means sensitive to the tempera-- ture of said medium, aregulator to predetermine and vary the effect of temperature upon saidmeans, a governor for said unit and actuatable by said thermostaticmeans, timing operates said valve.

mechanism, and means rendering said governor, but not said regulator,conditionable by said timing mechanism. I

5. In combination, a gas oven, a burner for hea-ting said `oven, a valvehaving a stationary body connected in a pipe line and having movableparts controlling the How of gas 'to said burner, timing mechanismremote from heat in said oven, thermostaticmechanismincluding a membersensitive to heat in said oven, connections whereby said timingmechanism operates said valve independently of said thermostaticmechanism, and lconnections wherebysaid thermostatic mechanism 6. A.combined time and temperature control for gas ranges comprising incombination with a heating burner, a thermostat disposed to be4sensitive to heat generated byl said burner, a timing mechanism, and avalve govl erning the supply of gasto said burner and connected bymechanicalparts both to said thermostat and to said timing mechanismandv actuatable in common ther-eb i 7. Iiicombination, 'a valveincluding a art movable to increase and to decrease a ow through avariable port in a conduit, timing mechanism, a non-yielding mechanicalypart constituting at-.o'ne point the sole means of operative connectionbetween said mecha- I n1sm,andv said valve, and thermo-dynamic means,also connected operatively with said valve part and solely by means ofsaid'nonfyielding mechanical part at said point in said connections. 1

8. In combination, a valve including a part movable to vary the `flowthrough a portkin a conduit, timin mechanism, a thermostatic device,anon-yie ding connecting member for 'operating said valve part, a'powertransmit- 4 ting medium between said member and said timing mechanism,and an operatively sepa-i rate power transmitting. medium between`mission parts including a means lfor mechanical slippage and connectingsaid mechanism with 'said valve member, a heatl governed device, andanother set of transmis- `,sion parts connecting said device with the;

, member, said means for mechanical slippage permitting said timemechanism alone to move said valve member by means of its said set oftransmission parts.

11. In combination `with thermal mechanism and timing mechanism foractuating in common a single conduit control, a member of said controlconnected by a yielding mechanism to be movable with said time actuatingmechanism when vacted upon by the latter,

and further connected by non-yielding mechanism to be moved relativeto\said time mechanism when acted upon by said thermal p mechanism.

12.v In combination with thermal mechanism andtiming mechanism foractuating in common a single conduit control, a member'of said controlconnected by a yieldii'ig` mechanismv to be movable with said thermalmechanism when acted upon by the latter,

vand further connected by non-yielding mechanismto be moved relative tosaid thermal mechanism when acted upon by said timing mechanism.

13. In a combined vtime and temperature control mechanism, a valveactuatable in common by time and temperature veffects working throughsaid mechanism, vmeans to set a portion of saidcombined mechanism 4sothat the actionlof temperature change upon lsaid valve shall be one of"degree andme'ans to set another portion of said combined mechanism sothat the action of time upon said valve shall be either to renderoperative or inoperative'upon said valve the said action -of temerature.

14. p n combination, a conduit control havmg full open and full closedositions, a timing'mechanism tending to e ect one or the other of saidpositions anda thermal mechanism connected to actuate saidcontrol tocause degrees of opening thereof intermediate its said two positions.

1 5.v In combination, a gas oven,a burner for heating saidoven, a valvehaving a stationarybody connected in al pipe line and 'having movableparts controlling the flowA of gas to said burner, timing mechanismremote fromheat in said oven, ther'mostatic mechanism including a membersensitive to heat in said oven, connections whereby` said timingmechanism operates said valveindependently of said thermostaticmechanism, connections wherebyjsaid thermostaticmechanism operates saidvalve, and a. hand setting device arranged to act between said'member ofthe thermostatic mechanism and the last said connection thereby to varythe eect of said thermostatic mechanism upon said valve responsive to agiven temperature in 'said oven.

16. A combined time and heat controlled x valve having in combination,a` single valve member` movable to open and to close a port in aconduit, time mechanism, a heat governed device, two sets oftransmission parts one of which connects said mechanism with said valvememberand the other of `which connects said device with said valve mem'-ber, each of saidfsets of transmission parts' having a means permittingmechanical slippage, thereby to allow the other set of transmissionparts to act independently for oper-` ation of said mechanism aloneor/of said device alone upon said valve member.

Signed at Pleasantville, New York, this 20th day of April, 1927.

` RAYMOND D. SMITH.

